1. Field of the Invention
The present invention relates generally to the field of camera devices and lens assemblies therefor, and more particularly to a novel concealable lens assembly for use primarily in digital cameras. The predominant current application for the inventive pop up prism lens assembly is in the production of high quality digital cameras, wherein small size, rugged construction and cost are all important factors.
2. Description of the Background Art
It is known in the art to use one or more prisms to redirect the optical path in a camera. Among other advantages, the use of a prism often allows the designer to make the camera package more compact than an entirely linear optical path would permit. Since positioning of the prism in relation to other lens components is critical in a high quality camera, it has been thought that the prism should be rigidly affixed within the camera housing. Also, it is believed that, prior to the present invention, there has been no apparent advantage in causing the prism to be movable within the camera housing.
It is also known in the prior art to provide a means to manually and/or automatically cover a camera lens when it is not in use. Usually, this means has included some sort of lens cap. Modern innovations in electronic cameras have included lenses which automatically retract when the camera is turned off, and this sort of arrangement is often accompanied by some sort of automatic closure mechanism which covers the opening into which the lens retracts.
It is also known in the prior art to use a drum type cam device to move lenses, as needed, within a camera. U.S. Pat. No. 6,670,989, issued to Kawanishi, et al., teaches an example of such a device.
It would be advantageous to have a method and or means to protect the lens of a camera, when it is not is use, which contributes to making the camera smaller and lighter, rather than requiring extra components and thereby making the camera larger, heavier, and more expensive to construct. It would also be advantageous to have a method and or means to protect the lens of a camera when it is not is use which provides a reliable relationship between surfaces of optical components in the lens system. It would also be advantageous to have a camera apparatus which would be simpler, more rugged, less expensive and/or optically superior to known prior art devices.
To the inventor's knowledge, no prior art device has successfully achieved the above described objectives. All prior art apparatus for retracting and/or protecting lens assemblies have negatively contributed to the size, weight and/or complexity of the camera, or else have not been as rugged and reliable as might be desired. All prior art apparatus for bringing camera optics into a “ready” position and/or for positioning a telephoto lens element have required relatively complex, large and expensive mechanisms, and a separate mechanism has been required to perform each of these functions.